Question 15
$ABCDE$ is a regular pentagon. A circle is drawn through it, tangent to $CD$ at $D$ and to $AB$ at $A$. What is the angle subtended at the circle's centre by the minor arc $AD$?
Interpret the source phrase “angle formed by the minor arc AD” as the measure of that arc, equivalently its central angle, not an inscribed angle.
Original figure, preserving all printed mathematical labels and the disclosed source-image discrepancy where applicable.
Interpret the source phrase “angle formed by the minor arc AD” as the measure of that arc, equivalently its central angle, not an inscribed angle.
Original figure, preserving all printed mathematical labels and the disclosed source-image discrepancy where applicable.